Glycolic menthyl ester.



UNITED ST TES.

PATENT OFFIC FRITZ HOFMANN AND J URGEN CALLSEN, OF ELBERFELD, GERMANY, ASSIGNORS TO FARBENFABRIKEN OF ELBERFELDCQ, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

QGLYCOLIC MENTHYL ESTER.

SPECIFICATION forming part of Letters Patent No. 707,110, dated August 19, 1902.

' Application filed A ril 29,1902, SerialNo. 105,209. (Specimens) To all whom it may concern.- I

Be :it, known that we, FRITZ HOFMANN and J iiRGEN OA'LLSEN, doctors of= philosophy, chemists, residing at Elber feld, Germany, (assignors to the F ARBENFABRIKEN or EL- BERFELD COMPANY, ofNew York,) have in- I vented a newiand.usefulImprovement in .Glycolic Menthyl Esters, of which the follow- 5. 6 parts o th mid L Parts Of Water hydrochloricacid gas isintroducedfor some ing is a specification.

Our invention relates to the-preparation of a new pharmaceutical productwhich is chemically the ester of menthol and glycolic acid, the glycolic menthyl ester of the formula: p y

and which according to our researches pospound consists in treating menthol or deriva- :tives. thereof with. glycolic 'acid. or derivatives thereof in any manner suitablelfor the method of esterification. menthyl ester thus produced represents White The new glycolic lustrous needles melting at 8Z-:centigrade. It is only sparingly soluble in water and readily soluble in most organic solvents. By the action of caustic alkalies or alkaline carbonates it is split up into menthol and glycolic .acid.

. The following examples will serve to illustrate the-manner in which our invention can be carried into practical effect. The parts are by weight:

Example I: 7.6parts of glycolic acidand 15. 6 parts of menthol are heatedfor about six hours at about175' centigrade. Subsequently the reaction mass is distilled in glycolide (O H O )a: and 15.6" parts of menthol is heated at about 200 centigrade for fromeight to ten hours. The reaction mass is tben' further treatedas described in Example I; i f 1 'Example'IlI: Into a mixture of 5.7 parts of the nitrile of glycolic acid,

hours while stirring. During this time the temperature is kept at about centigrade. .The glycolic menthyl esterthus produced is then isolated and purified in the manner described in Example I. V r

The new ester can also be prepared by heating with menthol glycolic anhydrid glycolide,

I oo O-CH I glycolic ethyl ester or the like, orby "heating a salt of glycolic acid, such assilver glycolv ate, 'with menthyl'iodid or the like.

Having now described our invention and in what manner the same isto be performed, what we claim'asnewfand desire to secure by LettersPatent, is-

thylester having'the formula y a p oooo n representing-white lustrous *needlesmeltin at 87c6ntigrade, which are only sparingly soluble-in water and readily solublein most organic solvents, beingsplitup into menthol The herein-described new glycolic men and glycolic acid when reacted upon by caus-' tic alkalies or alkaline carbonates and "exhibiting valuable therapeutic properties, sub- -scanti'allyashereinbefore described.

In testimony whereof we have signed our names in the presence of two subscribing witnesses.

FRITZ HOFMANN;

Witnesses:

O'r'ro KONIG, E IL BLOMBERG.

JIIRGEN OALLSEN. v 

